Pyrazoloazole type couplers give dyes having less unnecessary spectral absorption at about 430 n.m. induced from dyes formed by coupling with the oxidation product of paraphenylenediamine as compared to conventional 5-pyrazolone couplers and hence various pyrazoloazole type couplers have been proposed for improving the color reproduction of color light-sensitive materials.
For example, there are proposed pyrazolobenzimidazole skeletons described in U.S. Pat. Nos. 3,061,432, 3,369,897, etc., 1H-pyrazolo[3,2-c][1,2,4]triazole skeletons described in U.S. Pat. No. 3,725,067, etc., 1H-imidazo[1,2-b]pyrazole skeletons described in U.S. Pat. No. 4,500,630, etc., 1H-pyrazolo[1,5-b][1,2,4]triazole skeletons described in U.S. Pat. No. 4,540,654, etc., and 1H-pyrazolo[1,5-b]tetrazole skeletons described in Japanese Patent Application (OPI) No. 33,552/85 (the term "OPI" as used herein means as "unexamined published Japanese patent application").
The azomethine dyes induced from the pyrazoloazole couplers having these skeletons surely have less unnecessary absorption near 430 n.m. and show sharp foot cut of-the characteristic curve at a long wavelength side, which are preferably for color reproduction, but they are yet insufficient for color photographic materials since the coupling speed of the couplers with the oxidation product of a developing agent is slow and also the light fastness of color images formed is low.